SQL Dates Selection - sql

I Have a OPL_Dates Table with Start Date and End Dates as Below:
dbo.OPL_Dates
ID Start_date End_date
--------------------------------------
12345 1975-01-01 2001-12-31
12345 1989-01-01 2004-12-31
12345 2005-01-01 NULL
12345 2007-01-01 NULL
12377 2009-06-01 2009-12-31
12377 2013-02-07 NULL
12377 2010-01-01 2012-01-01
12489 2011-12-31 NULL
12489 2012-03-01 2012-04-01
The Output I am looking for is:
ID Start_date End_date
-------------------------------------
12345 1975-01-01 2004-12-31
12345 2005-01-01 NULL
12377 2009-06-01 2009-12-31
12377 2010-01-01 2012-01-01
12377 2013-02-07 NULL
12489 2011-12-31 NULL
Basically, I want to show the gap between the OPL periods(IF Any) else I need min of Start Date and Max of End Dates, for a particular ID.NULL means Open-Ended Date which can be converted to "9999-12-31".

The following pretty much does what you want:
with p as (
select v.*, sum(inc) over (partition by v.id order by v.dte) as running_inc
from t cross apply
(values (id, start_date, 1),
(id, coalesce(end_date, '2999-12-31'), -1)
) v(id, dte, inc)
)
select id, min(dte), max(dte)
from (select p.*, sum(case when running_inc = 0 then 1 else 0 end) over (partition by id order by dte desc) as grp
from p
) p
group by id, grp;
Note that it changes the "inifinite" end date from NULL to 2999-12-31. This is a convenience, because NULL orders first in SQL Server ascending sorts.
Here is a SQL Fiddle.
What is this doing? It is unpivoting the dates into a single column, with a 1/-1 flag (inc) indicating whether the record is a start or end. The running sum of this flag then indicates the groups that should be combined. When the running sum is 0, then a group has ended. To include the end date in the right group, a reverse running sum is needed -- but that's a detail.

Related

replace First record date with 1900-01-01 Last record = 2999-01-01

say I have the following table that is for the same person:
Id
Start_date
End_date
1
2007-01-01
2007-12-31
1
2008-01-01
2009-12-31
1
2010-01-01
2011-07-31
what I want is to have the first date replaced with 1900-01-01 and last date with 2999-01-01
I achieved that with following but wanted to know if there's anything better:
CASE WHEN Start_date = MIN(Start_date) OVER (PARTITION BY id) THEN '1900-01-01' END AS newdate
Ideas?
So you CASE state was quite close, if you are want to replace the first start and the last end, you just needed to put an ELSE clause in there.
myself I am a fan of the IFF form instead of the CASE form. And I often like to use ROW_NUMBER = 1 verse = MAX But MAX is faster to compute distributed. So if you don't have duplicate values I would stick with that.
so here are some options:
with data(Id,Start_date,End_date) as (
select * from values
(1, '2007-01-01'::date, '2007-12-31'::date),
(1, '2008-01-01'::date, '2009-12-31'::date),
(1, '2010-01-01'::date, '2011-07-31'::date)
)
select
id,
start_date,
end_date,
CASE WHEN Start_date = MIN(Start_date) OVER (PARTITION BY id) THEN '1900-01-01' END AS newdate_A,
IFF(start_date = MIN(Start_date) over (partition by id), '1900-01-01', start_date ) as newdate_b,
CASE WHEN Start_date = MIN(Start_date) OVER (PARTITION BY id) THEN '1900-01-01' ELSE start_date END AS newdate_c,
IFF(ROW_NUMBER() over (partition by id order by start_date) = 1, '1900-01-01', start_date ) as newdate_d,
CASE WHEN end_date = MAX(end_date) OVER (PARTITION BY id) THEN '2999-01-01' ELSE end_date END AS new_end_date
from data
order by start_date;
ID
START_DATE
END_DATE
NEWDATE_A
NEWDATE_B
NEWDATE_C
NEWDATE_D
NEW_END_DATE
1
2007-01-01
2007-12-31
1900-01-01
1900-01-01
1900-01-01
1900-01-01
2007-12-31
1
2008-01-01
2009-12-31
null
2008-01-01
2008-01-01
2008-01-01
2009-12-31
1
2010-01-01
2011-07-31
null
2010-01-01
2010-01-01
2010-01-01
2999-01-01
The first three columns are just your data, then newdate_a is your current code. newdate_c and new_end_date are how I believe you are want the data to be.
Thus I think you are asking for this:
select
id,
CASE WHEN Start_date = MIN(Start_date) OVER (PARTITION BY id) THEN '1900-01-01' ELSE start_date END AS new_start_date,
CASE WHEN end_date = MAX(end_date) OVER (PARTITION BY id) THEN '2999-01-01' ELSE end_date END AS new_end_date
from data
order by start_date;
ID
NEW_START_DATE
NEW_END_DATE
1
1900-01-01
2007-12-31
1
2008-01-01
2009-12-31
1
2010-01-01
2999-01-01

Oracle SQL - Select users between two date by month

I am learning SQL and I was wondering how to select active users by month, depending on their starting and ending date (both timestamp(6)). My table looks like this:
Cust_Num | Start_Date | End_Date
1 | 2018-01-01 | 2019-01-01
2 | 2018-01-01 | NULL
3 | 2019-01-01 | 2019-06-01
4 | 2017-01-01 | 2019-03-01
So, counting the active users by month, I should have an output like:
As of. | Count
2018-06-01 | 3
...
2019-02-01 | 3
2019-07-01 | 1
So far, I do a manual operation by entering each month:
Select
201906,
count(distinct a.cust_num)
From
active_users a
Where
to_date(‘20190630’,’yyyymmdd) between a.start_date and nvl (a.end_date, ‘31-dec-9999)
union all
Select
201905,
count(distinct a.cust_num)
From
active_users a
Where
to_date(‘20190531’,’yyyymmdd) between a.start_date and nvl (a.end_date, ‘31-dec-9999)
union all
...
Not very optimized and sustainable if I want to enter 10 years ao 120 months lol.
Any help is welcome. Thanks a lot!
This query shows the active-user-count effective as-of the end of the month.
How it works:
Convert each input row (with StartDate and EndDate value) into two rows that represent a point-in-time when the active-user-count incremented (on StartDate) and decremented (on EndDate). We need to convert NULL to a far-off date value because NULL values are sorted before instead of after non-NULL values:
This makes your data look like this:
OnThisDate Change
2018-01-01 1
2019-01-01 -1
2018-01-01 1
9999-12-31 -1
2019-01-01 1
2019-06-01 -1
2017-01-01 1
2019-03-01 -1
Then we simply SUM OVER the Change values (after sorting) to get the active-user-count as of that specific date:
So first, sort by OnThisDate:
OnThisDate Change
2017-01-01 1
2018-01-01 1
2018-01-01 1
2019-01-01 1
2019-01-01 -1
2019-03-01 -1
2019-06-01 -1
9999-12-31 -1
Then SUM OVER:
OnThisDate ActiveCount
2017-01-01 1
2018-01-01 2
2018-01-01 3
2019-01-01 4
2019-01-01 3
2019-03-01 2
2019-06-01 1
9999-12-31 0
Then we PARTITION (not group!) the rows by month and sort them by their date so we can identify the last ActiveCount row for that month (this actually happens in the WHERE of the outermost query, using ROW_NUMBER() and COUNT() for each month PARTITION):
OnThisDate ActiveCount IsLastInMonth
2017-01-01 1 1
2018-01-01 2 0
2018-01-01 3 1
2019-01-01 4 0
2019-01-01 3 1
2019-03-01 2 1
2019-06-01 1 1
9999-12-31 0 1
Then filter on that where IsLastInMonth = 1 (actually, where ROW_COUNT() = COUNT(*) inside each PARTITION) to give us the final output data:
At-end-of-month Active-count
2017-01 1
2018-01 3
2019-01 3
2019-03 2
2019-06 1
9999-12 0
This does result in "gaps" in the result-set because the At-end-of-month column only shows rows where the Active-count value actually changed rather than including all possible calendar months - but that's ideal (as far as I'm concerned) because it excludes redundant data. Filling in the gaps can be done inside your application code by simply repeating output rows for each additional month until it reaches the next At-end-of-month value.
Here's the query using T-SQL on SQL Server (I don't have access to Oracle right now). And here's the SQLFiddle I used to come to a solution: http://sqlfiddle.com/#!18/ad68b7/24
SELECT
OtdYear,
OtdMonth,
ActiveCount
FROM
(
-- This query adds columns to indicate which row is the last-row-in-month ( where RowInMonth == RowsInMonth )
SELECT
OnThisDate,
OtdYear,
OtdMonth,
ROW_NUMBER() OVER ( PARTITION BY OtdYear, OtdMonth ORDER BY OnThisDate ) AS RowInMonth,
COUNT(*) OVER ( PARTITION BY OtdYear, OtdMonth ) AS RowsInMonth,
ActiveCount
FROM
(
SELECT
OnThisDate,
YEAR( OnThisDate ) AS OtdYear,
MONTH( OnThisDate ) AS OtdMonth,
SUM( [Change] ) OVER ( ORDER BY OnThisDate ASC ) AS ActiveCount
FROM
(
SELECT
StartDate AS [OnThisDate],
1 AS [Change]
FROM
tbl
UNION ALL
SELECT
ISNULL( EndDate, DATEFROMPARTS( 9999, 12, 31 ) ) AS [OnThisDate],
-1 AS [Change]
FROM
tbl
) AS sq1
) AS sq2
) AS sq3
WHERE
RowInMonth = RowsInMonth
ORDER BY
OtdYear,
OtdMonth
This query can be flattened into fewer nested queries by using aggregate and window functions directly instead of using aliases (like OtdYear, ActiveCount, etc) but that would make the query much harder to understand.
I have created the query which will give the result of all the months starting from the minimum start date in the table till maximum end date.
You can change it using adding one condition in WHERE clause.
-- table creation
CREATE TABLE ACTIVE_USERS (CUST_NUM NUMBER, START_DATE DATE, END_DATE DATE)
-- data creation
INSERT INTO ACTIVE_USERS
SELECT * FROM
(
SELECT 1, DATE '2018-01-01', DATE '2019-01-01' FROM DUAL UNION ALL
SELECT 2, DATE '2018-01-01', NULL FROM DUAL UNION ALL
SELECT 3, DATE '2019-01-01', DATE '2019-06-01' FROM DUAL UNION ALL
SELECT 4, DATE '2017-01-01', DATE '2019-03-01' FROM DUAL
)
-- data in the actual table
SELECT * FROM ACTIVE_USERS ORDER BY CUST_NUM;
CUST_NUM START_DATE END_DATE
---------- ---------- ----------
1 2018-01-01 2019-01-01
2 2018-01-01
3 2019-01-01 2019-06-01
4 2017-01-01 2019-03-01
Query to fetch desired result
WITH CTE ( START_DATE, END_DATE ) AS
(
SELECT
ADD_MONTHS( START_DATE, LEVEL - 1 ),
ADD_MONTHS( START_DATE, LEVEL ) - 1
FROM
(
SELECT
MIN( START_DATE ) AS START_DATE,
MAX( END_DATE ) AS END_DATE
FROM
ACTIVE_USERS
)
CONNECT BY LEVEL <= CEIL( MONTHS_BETWEEN( END_DATE, START_DATE ) ) + 1
)
--
--
SELECT
C.START_DATE,
COUNT(1) AS CNT
FROM
CTE C
JOIN ACTIVE_USERS D ON
(
C.END_DATE BETWEEN
D.START_DATE
AND
CASE
WHEN D.END_DATE IS NOT NULL THEN D.END_DATE
ELSE C.END_DATE
END
)
GROUP BY
C.START_DATE
ORDER BY
C.START_DATE;
-- output --
START_DATE CNT
---------- ----------
2017-01-01 1
2017-02-01 1
2017-03-01 1
2017-04-01 1
2017-05-01 1
2017-06-01 1
2017-07-01 1
2017-08-01 1
2017-09-01 1
2017-10-01 1
2017-11-01 1
START_DATE CNT
---------- ----------
2017-12-01 1
2018-01-01 3
2018-02-01 3
2018-03-01 3
2018-04-01 3
2018-05-01 3
2018-06-01 3
2018-07-01 3
2018-08-01 3
2018-09-01 3
2018-10-01 3
START_DATE CNT
---------- ----------
2018-11-01 3
2018-12-01 3
2019-01-01 3
2019-02-01 3
2019-03-01 2
2019-04-01 2
2019-05-01 2
2019-06-01 1
30 rows selected.
Cheers!!

How do I select start_date and corresponding end_date

The data input in the table in Oracle is as below. That is start_date is in one row but the end_date is in the next row for a account number. Want to align the start date and end date in the same row. I tried using lead function and it doesn't seem to work. I am using Oracle 11g. Can you please help me with this.
ACCT_NUM ACTV_TMST START_DATE END_DATE
1234 11/22/2006 2:12:13.928230 PM 11/22/2006 00:00:00 NULL
1234 11/28/2006 7:35:05.659595 AM NULL 11/28/2006
1234 12/22/2008 3:00:47.864811 PM 12/22/2008 00:00:00 NULL
1234 12/26/2008 3:34:28.776394 PM NULL 12/26/2008 00:00:00
1234 02/18/2016 9:22:35.746829 AM 02/18/2016 00:00:00 NULL
1234 02/23/2016 9:03:35.295622 AM NULL 02/23/2016 00:00:00
I need an output like
ACCT_NUM START_DATE END_DATE
1234 11/22/2006 00:00:00 11/28/2006 00:00:00
1234 12/22/2008 00:00:00 12/26/2008 00:00:00
1234 02/18/2016 00:00:00 02/23/2016 00:00:00
Thanks.
You can use ORACLE's row_number window function:
SELECT s.acct_num,
max(s.start_date) as start_date,
max(s.end_date) as end_date
FROM(
SELECT t.acct_num,
t.start_date,
row_number() OVER(PARTITION BY t.acct_num ORDER BY t.start_date) as sd_rnk,
t.end_date,
row_number() OVER(PARTITION BY t.acct_num ORDER BY t.end_date) as ed_rnk
FROM YourTable t) s
GROUP BY acct_num,
CASE WHEN t.start_date is null then ed_rnk else sd_rnk end
This will basically rank each row, first start_date 1 , second will get 2. Same goes for end_date, first will get 1 second 2...
Then, you will group by this results (acct_num , end_date_rank / start_date_rank) and use an aggregation function to unite them into 1 row.

start date end date combine rows

In Redshift, through SQL script want to consolidate monthly records as long as gap between the end date of first and the start date of the next record is 32 days or less (<=32) into single record with minimum startdate of continuous month as output startdate and maximum of end date of continuous month as output enddate.
The below input data refers to the table's data and also listed the expected output. The input data is listed ORDER BY ID,STARTDT,ENDDT in ASC.
For example, in below table, consider ID 100, the gab between the end of the first record and start of the next record <=32, however gap between the second record end date and third records start date falls more than 32 days, hence the first two records to be consolidate into one record i.e. (ID),MIN(STARTSDT),MAX(ENDDT) which corresponds to first record in the expected output. Similarly gab between 3 and 4 record in the input data falls within the 32 days and thus these 2 records to be consolidated into single records which corresponds to the second record in the expected output.
INPUT DATA:
ID STARTDT ENDDT
100 2000-01-01 2000-01-31
100 2000-02-01 2000-02-29
100 2000-05-01 2000-05-31
100 2000-06-01 2000-06-30
100 2000-09-01 2000-09-30
100 2000-10-01 2000-10-31
101 2012-06-01 2012-06-30
101 2012-07-01 2012-07-31
102 2000-01-01 2000-01-31
103 2013-03-01 2013-03-31
103 2013-05-01 2013-05-31
EXPECTED OUTPUT:
ID MIN_STARTDT MAX_END_DT
100 2000-01-01 2000-02-29
100 2000-05-01 2000-06-30
100 2000-09-01 2000-10-31
101 2012-06-01 2012-07-31
102 2000-01-01 2000-01-31
103 2013-03-01 2013-03-31
103 2013-05-01 2013-05-31
You can do this in steps:
Use a join to identify where two adjacent records should be combined.
Then do a cumulative sum to assign all such adjacent records a grouping identifier.
Aggregate.
It looks like:
select id, min(startdt), max(enddte)
from (select t.*,
count(case when tprev.id is null then 1 else 0 end) over
(partition by t.idid
order by t.startdt
rows between unbounded preceding and current row
) as grp
from t left join
t tprev
on t.id = tprev.id and
t.startdt = tprev.enddt + interval '1 day'
) t
group by id, grp;
The question is very similar to this one and my answer is also similar: Fetch rows based on condition
The gist of the idea is to use Window Functions to identify transitions between period (events which are less than 33 days apart), and then do some filtering to remove the rows within the period, and then Window Functions again.
Complete solution:
SELECT
id,
startdt AS period_start,
period_end
FROM (
SELECT
id,
startdt,
enddt,
lead(enddt, 1)
OVER (PARTITION BY id
ORDER BY enddt) AS period_end,
period_boundary
FROM (
SELECT
id,
startdt,
enddt,
CASE WHEN period_switch = 0 AND reverse_period_switch = 1
THEN 'start'
ELSE 'end' END AS period_boundary
FROM (
SELECT
id,
startdt,
enddt,
CASE WHEN datediff(days, enddt, lead(startdt, 1)
OVER (PARTITION BY id
ORDER BY enddt ASC)) > 32
THEN 1
ELSE 0 END AS period_switch,
CASE WHEN datediff(days, lead(enddt, 1)
OVER (PARTITION BY id
ORDER BY enddt DESC), startdt) > 32
THEN 1
ELSE 0 END AS reverse_period_switch
FROM date_test
)
AS sessioned
WHERE period_switch != 0 OR reverse_period_switch != 0
UNION
SELECT -- adding start rows without transition
id,
startdt,
enddt,
'start'
FROM (
SELECT
id,
startdt,
enddt,
row_number()
OVER (PARTITION BY id
ORDER BY enddt ASC) AS row_num
FROM date_test
) AS with_row_number
WHERE row_num = 1
UNION
SELECT -- adding end rows without transition
id,
startdt,
enddt,
'end'
FROM (
SELECT
id,
startdt,
enddt,
row_number()
OVER (PARTITION BY id
ORDER BY enddt desc) AS row_num
FROM date_test
) AS with_row_number
WHERE row_num = 1
) AS with_boundary -- data set containing start/end boundaries
) AS with_end -- data set where end date is propagated into the start row of the period
WHERE period_boundary = 'start'
ORDER BY id, startdt ASC;
Note that in your expected output, you had a row for 103 2013-05-01 2013-05-31, however its start date is 31 days apart from end date of the previous row, so this row should instead be merged with the previous row for id 103 according to your requirements.
So the output that I get looks like this:
id start end
100 2000-01-01 2000-02-29
100 2000-05-01 2000-06-30
100 2000-09-01 2000-10-31
101 2012-06-01 2012-07-31
102 2000-01-01 2000-01-31
103 2013-03-01 2013-05-31

Find From/To Dates across multiple rows - SQL Postgres

I want to be able to "book" within range of dates, but you can't book across gaps of days. So booking across multiple rates is fine as long as they are contiguous.
I am happy to change data structure/index, if there are better ways of storing start/end ranges.
So far I have a "rates" table which contains Start/End Periods of time with a daily rate.
e.g. Rates Table.
ID Price From To
1 75.00 2015-04-12 2016-04-15
2 100.00 2016-04-16 2016-04-17
3 50.00 2016-04-18 2016-04-30
For the above data I would want to return:
From To
2015-04-12 2016-4-30
For simplicity sake it is safe to assume that dates are safely consecutive. For contiguous dates To is always 1 day before from.
For the case there is only 1 row, I would want it to return the From/To of that single row.
Also to clarify if I had the following data:
ID Price From To
1 75.00 2015-04-12 2016-04-15
2 100.00 2016-04-17 2016-04-18
3 50.00 2016-04-19 2016-04-30
4 50.00 2016-05-01 2016-05-21
Meaning where there is a gap >= 1 day it would count as a separate range.
In which case I would expect the following:
From To
2015-04-12 2016-04-15
2015-04-17 2016-05-21
Edit 1
After playing around I have come up with the following SQL which seems to work. Although I'm not sure if there are better ways/issues with it?
WITH grouped_rates AS
(SELECT
from_date,
to_date,
SUM(grp_start) OVER (ORDER BY from_date, to_date) group
FROM (SELECT
gite_id,
from_date,
to_date,
CASE WHEN (from_date - INTERVAL '1 DAY') = lag(to_date)
OVER (ORDER BY from_date, to_date)
THEN 0
ELSE 1
END grp_start
FROM rates
GROUP BY from_date, to_date) AS start_groups)
SELECT
min(from_date) from_date,
max(to_date) to_date
FROM grouped_rates
GROUP BY grp;
This is identifying contiguous overlapping groups in the data. One approach is to find where each group begins and then do a cumulative sum. The following query adds a flag indicating if a row starts a group:
select r.*,
(case when not exists (select 1
from rates r2
where r2.from < r.from and r2.to >= r.to or
(r2.from = r.from and r2.id < r.id)
)
then 1 else 0 end) as StartFlag
from rate r;
The or in the correlation condition is to handle the situation where intervals that define a group overlap on the start date for the interval.
You can then do a cumulative sum on this flag and aggregate by that sum:
with r as (
select r.*,
(case when not exists (select 1
from rates r2
where (r2.from < r.from and r2.to >= r.to) or
(r2.from = r.from and r2.id < r.id)
)
then 1 else 0 end) as StartFlag
from rate r
)
select min(from), max(to)
from (select r.*,
sum(r.StartFlag) over (order by r.from) as grp
from r
) r
group by grp;
CREATE TABLE prices( id INTEGER NOT NULL PRIMARY KEY
, price MONEY
, date_from DATE NOT NULL
, date_upto DATE NOT NULL
);
-- some data (upper limit is EXCLUSIVE)
INSERT INTO prices(id, price, date_from, date_upto) VALUES
( 1, 75.00, '2015-04-12', '2016-04-16' )
,( 2, 100.00, '2016-04-17', '2016-04-19' )
,( 3, 50.00, '2016-04-19', '2016-05-01' )
,( 4, 50.00, '2016-05-01', '2016-05-22' )
;
-- SELECT * FROM prices;
-- Recursive query to "connect the dots"
WITH RECURSIVE rrr AS (
SELECT date_from, date_upto
, 1 AS nperiod
FROM prices p0
WHERE NOT EXISTS (SELECT * FROM prices nx WHERE nx.date_upto = p0.date_from) -- no preceding segment
UNION ALL
SELECT r.date_from, p1.date_upto
, 1+r.nperiod AS nperiod
FROM prices p1
JOIN rrr r ON p1.date_from = r.date_upto
)
SELECT * FROM rrr r
WHERE NOT EXISTS (SELECT * FROM prices nx WHERE nx.date_from = r.date_upto) -- no following segment
;
Result:
date_from | date_upto | nperiod
------------+------------+---------
2015-04-12 | 2016-04-16 | 1
2016-04-17 | 2016-05-22 | 3
(2 rows)